A silicon carbide umosfet device with integrated tjbs

Abstract

The invention relates to a silicon carbide UMOSFET device integrating TJBS, comprising: N+ substrate region, N-epitaxy region, P-well region, N+ injection region, first P+ injection region, second P+ injection region, gate, source electrode and drain, wherein the second P+ implantation region is spaced from the first P+ implantation region and has the same depth, the first P+ implantation region is provided with a first trench, and the second P+ implantation region is provided with a second trench, The depth of the gate is greater than the depth of the P-well region and less than the depth of the first P+ implantation region, and the interface between the source and the P-well region, the N+ implantation region, the first P+ implantation region, and the second P+ implantation region is an ohmic contact, The interface between the source and the N-epi region is a Schottky contact. In the device of the present invention, a trench structure is introduced into the Schottky diode structure integrated in the device, so that the depths of the first P+ implantation region and the second P+ implantation region are increased, and the thinner N-epitaxy formed by etching P+ implantation is carried out on the surface of the region, which makes the depth of the P+ implantation region larger and improves the avalanche resistance of the device.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, and in particular relates to a silicon carbide UMOSFET device integrating TJBS. Background technique [0002] In recent years, with the continuous development of power electronic systems, higher requirements have been placed on the power devices in the system. Silicon (Si)-based power electronic devices have been unable to meet the requirements of system applications due to the limitations of the material itself. As a representative of the third-generation semiconductor material, silicon carbide (SiC) materials are far better than silicon materials in many characteristics. Silicon carbide MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor, Metal-Oxide-Semiconductor Field-Effect Transistor) device, as a commercialized device in recent years, has an alternative in terms of on-resistance, switching time, switching loss and heat dissipation performance. The huge potential of the existi...

AI Technical Summary

Problems solved by technology

However, due to the large bandgap of silicon carbide materials, the turn-on voltage of the parasitic PiN diodes integrated in silicon carbide UMOSFET devices is mostly around 3V, which cannot provide freewheeling for the device itself, resulting in the internal freewheeling capability of silicon carbide UMOSFET devices. weaker

Therefore, in power electronic system applications such as full bridges, an additional Schottky diode is often used in antiparallel as a freewheeling diode, which greatly increases the complexity and cost of the circuit system.

In addition, in the blocking mode, a series of reliability problems will be caused due to the strong electric field of the gate oxide at the corner of the trench

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